Crack Stitching – Hidden Strength

When cracks were found in the external walls of six residential apartment blocks in Croydon, Surrey,Twistfix Registered Contractor Structures SE Ltd was called on to design a cost effective masonry repair solution for crack stitching and movement control.

The Structures SE engineer devised a repair scheme that was sympathetic to the fabric of the building and offered minimal disturbance to the residents.  Natural building movement were accommodated by the introduction of vertical joints, which were added by cutting through the external brick skin.  Twistfix remedial wall ties were used to stitch the brick façade to the main structure either side of the new joints.

Structures SE set about providing a durable structural repair system for crack stitching and reinforcing the masonry walls by installing high tensile Twistfix bed joint reinforcement bars embedded in masonry repair grout.

The stainless steel crack stitching bars were bonded into channelled-out mortar beds with the high strength grout, stitching brickwork across each crack at regular intervals.. The mortar beds were then made good by repointing to fully conceal the repair.

“The cracked walls of the apartment blocks were strengthened using a variety of ‘easy to install’ Twistfix products,” explained Steve Musslewhite of Structures SE Ltd, “the client was delighted that the structural integrity of the apartment blocks was fully restored, that the masonry repair system was hidden within the walls and the whole scheme was cost effective”

Structures SE Ltd is a Twistfix Registered Contractor offering masonry repairs and wall tie replacement skills in London and in the South East regions.

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